The reproduction of a recorded signal of a hard disk drive is performed by using a magnetic sensor to sense a leakage magnetic field from recorded bits written to a magnetic disk. The size of each recorded bit is becoming extremely small as the recording density is increased. Therefore, both a smaller magnetic sensor and higher sensitivity are desirable.
A spin-valve element has been proposed as a magnetic sensor that can be provided in a micro gap between magnetic shields. However, for such a spin-valve element, it is desirable to develop a structure to make even further size reductions possible.